New Simple Semigrorps

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基于灰色关联分析的双基点评价方法

依据灰色系统理论关联分析的基本原理，演绎出双基点评价方法．理想点与非理想点不是从比选方案内部取得，它们的选取充分考虑和利用了已有的信息，使得评判更切合实际．     

Banach~*上代数的上理想与子上代数

在文[1]中定义上乘运算,半同态,从而定义了Banach~*上代数。本文进一步讨论Banach~*上代数的上理想与上子代数。将它们置于空间偶对中考虑,给出了C~*上代数A与其对偶B~*代数A~*(及C~*代数A与其对偶B~*上代数A~*)的上理想与子代数,上子代数与理想之间的对偶关系,进一步明确了在拓扑结构下这种代数结构的对称性。     

理想与现实——对西双版纳建筑创作的思考

本文联系西双版纳的建筑创作,对当地地域文化、建筑形式创作方法和建筑创作的指导思想进行了一些思考,提出了创造理想而又现实的建筑环境应注意的问题。     

翻斗车的行车制动性能分析

翻斗车有前桥制动和四轮制动两种型式。仅前驱动桥制动,其行车制动性能计算不同于汽车。四轮制动的翻斗车,其空载、满载理想制动力分配曲线与汽车恰相反。     

Density and Thermal Expansion of Liquid Au-Cu Alloys

The density of liquid Cu-Au alloys is measured using the technique of electromagnetic levitation, which entails producing a shadow image of the sample. The shadow is recorded by a digital CCD-camera, and the volume of the sample is calculated by an image processing algorithm. The density and thermal expansion of several alloys and the pure elements copper and gold are investigated at various temperatures above their melting points. In addition, the densities are also investigated as a function of the gold concentration at constant temperature. The measured values agree with literature data and with predictions obtained by molecular dynamics. It was found from data analysis that the ideal solution model applies.     

Vapor-Phase Helmholtz Equation for HFC-227ea from Speed-of-Sound Measurements

This work presents measurements of the speed-of-sound in the vapor phase of 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea). The measurements were obtained in a stainless-steel spherical resonator with a volume of 900 cm³ at temperatures between 260 and 380 K and at pressures up to 500 kPa. Ideal-gas heat capacities and acoustic virial coefficients are directly produced from the data. A Helmholtz equation of state of high accuracy is proposed, whose parameters are directly obtained from speed-of-sound data fitting. The ideal-gas heat capacity data are fit by a functions and used when fitting the Helmholtz equation for the vapor phase. From this equation of state other thermodynamic state function are derived. Due to the high accuracy of the equation, only very precise experimental data are suitable for the model validation and only density measurements have these requirements. A very high accuracy is reached in density prediction, showing the obtained Helmholtz equation to be very reliable. The deduced vapor densities are furthermore compared with those obtained from acoustic virial coefficients with the temperature dependences calculated from hard-core square-well potentials.     

人居环境“阅读”——北京四合院居住文化

四合院建筑文化作为中华民族的特征之一,具有十分悠久的历史渊源,早在辽代就已经出现了,它不仅反映了中华民族的居住文化,也体现了一种“天然合一”的人文关系,本文就北京的四合院为例,浅析了它的历史背景和文化内涵。     

计算机辅助设计在工业设计的应用状况及发展前景

在工业设计进行的流程中,计算机辅助设计悄然的穿插在每一个相对独立的主题活动之中.从一个完整的设计流程审视,计算机辅助设计的作用显而易见.它在设计流程数据管理,产品效果表现以及计算机辅助模型制作等广泛应用,发挥了工具化的作用.在应用过程中,促进了其自身的发展和工业设计的发展.     

凰蛔柿戏ā⒐δ芊ā⑶呦喙胤ê妥畹湍昶

njiang Institute of Ecology and Geography,CAS Urumqi,830011,Xinjiang,China;2 Agriculture Technologg Service Station of the Sixth Agriculture Division,XPCC Wujiagu 831300,Xinjiang,China;3 Arboretum of Urumqi City,Urumqi 830011,Xinjiang,China)The lake plays an important role in maintaining the ecological balance.A study on the lowest ecological water level of lake is significant in solving the ecological degeneration of lake in China.This paper analyzes six kinds of calculation methods of the lowest ecological water level of lake: the yea